/*
 *   This program is free software: you can redistribute it and/or modify
 *   it under the terms of the GNU General Public License as published by
 *   the Free Software Foundation, either version 3 of the License, or
 *   (at your option) any later version.
 *
 *   This program is distributed in the hope that it will be useful,
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *   GNU General Public License for more details.
 *
 *   You should have received a copy of the GNU General Public License
 *   along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

/*
 *    DatabaseConnection.java
 *    Copyright (C) 2004-2012 University of Waikato, Hamilton, New Zealand
 *
 */

package weka.core.converters;

import java.io.File;
import java.sql.DatabaseMetaData;
import java.sql.SQLException;
import java.util.Properties;

import weka.experiment.DatabaseUtils;

/**
 * Connects to a database.
 *
 * @author Len Trigg (trigg@cs.waikato.ac.nz)
 * @author Stefan Mutter (mutter@cs.waikato.ac.nz)
 * @version $Revision$
 */
public class DatabaseConnection extends DatabaseUtils {

    /** for serialization */
    static final long serialVersionUID = 1673169848863178695L;

    /**
     * Sets up the database drivers.
     *
     * @throws Exception if an error occurs
     */
    public DatabaseConnection() throws Exception {
        super();
    }

    /**
     * Reads the properties from the specified file and sets up the database
     * drivers.
     *
     * @param propsFile the props file to load, ignored if null or pointing to a
     *                  directory
     * @throws Exception if an error occurs
     */
    public DatabaseConnection(File propsFile) throws Exception {
        super(propsFile);
    }

    /**
     * Uses the specified properties to set up the database drivers.
     *
     * @param props the properties to use, ignored if null
     * @throws Exception if an error occurs
     */
    public DatabaseConnection(Properties props) throws Exception {
        super(props);
    }

    /**
     * Returns the underlying properties object.
     * 
     * @return the properties object
     */
    public Properties getProperties() {
        return PROPERTIES;
    }

    /**
     * Check if the property checkUpperCaseNames in the DatabaseUtils file is set to
     * true or false.
     *
     * @return true if the property checkUpperCaseNames in the DatabaseUtils file is
     *         set to true, false otherwise.
     */
    public boolean getUpperCase() {
        return m_checkForUpperCaseNames;
    }

    /**
     * Gets meta data for the database connection object.
     *
     * @return the meta data.
     * @throws Exception if an error occurs
     */
    public DatabaseMetaData getMetaData() throws Exception {
        if (!isConnected())
            throw new IllegalStateException("Not connected, please connect first!");

        return m_Connection.getMetaData();
    }

    /**
     * Dewtermines if the current query retrieves a result set or updates a table
     *
     * @return the update count (-1 if the query retrieves a result set).
     * @throws SQLException if an error occurs
     */
    public int getUpdateCount() throws SQLException {
        if (!isConnected())
            throw new IllegalStateException("Not connected, please connect first!");

        return m_PreparedStatement.getUpdateCount();
    }

    
}
